In earlier generations, few babies and children wore earrings. But today baby earrings and children's earrings are commonplace in the playground/school/shopping centres. A more affluent society and changing attitudes, most likely the reasons.
While most children over the age of 5 appear to have their ears pierced, it's mainly the option of piercing a baby's ears that causes concern (and even contention in mothers' groups.) A bit of research shows no medical reason why it shouldn't be done, though paediatricians seem to agree that after the age of 3 months, when the baby's immune system can cope better if infection occurs, is safest.
So long as instructions are followed, wtih daily cleaning of the piercings, there should be no problem. Baby earrings can be small and insignificant or they can be bright and sparkly. Ensure the rods are short and the earring light, for the comfort of baby and she will probably not even know she's wearing earrings.
Children can often take care of their own daily cleaning. I know my two older grandchildren did. They were five when they had their ears pierced. The little one will have her ears pierced too, if she wants, when she's five. It's good for them to take responsibility for their own new piercings.
These days instructions include not turning the earrings daily. In years gone by, it was considered appropriate to turn the earrings daily, but it's now advised to leave them be, let the healing take place fully, then turn them after 30-40 days.
Children's earrings are only slightly larger than baby earrings. Again, short rods are necessary, and tightly fitted "nuts" to ensure any fiddling doesn't result in a lost earring.
At Baby Jewels, we find, of all children's jewellery, children's earrings are the most popular. They aren't as expensive as children's bracelets, and generally, children love their earrings best!